Skip hoisting mechanism for concrete mixers



July .14, 1931.- E. H. LlcHTl-:NBERG 1,814,564

SKIP HOISTING MECHANISM FOR CONCRETE MIXERS EH. Lichenb j- ATTORNEYS July 14, 1931. E. H. LICHTENBERG 1,814,564

SKIP HOISTING MECHANISM FOR CONCRETE MIXERS Filed sept. 5, 1929 2 sheets-'sheet 2.

Patented July 14, 19x31 i orrlce i ERICH n, LICHTENJSEEG, or MLWAUKEE, WIscoN'sI-N, A'ss'rerlxrole'fro Kennemer Coll!- QEANYQQFJVILWAUKEE., WISGQNsLN, A oonroian'rron o smiI Hors'rrNetMneHAnrsM sonV ooHcRE'rnMI-xiens f Avpp'licationled September Concrete mixing-apparatus of the type now generally known-in .Whicha cabley operF ated loading skip Yfor charging the noioring drum is employed, has .customarily e111'- bodied high superstructure lfromeWork, by -meensof Whiehfit has been possible@ read'- ly obtain a suicientelevation of the charging skip by its' operating cable toeiect the charging of the aggregate materials .into the mixing drunLl l o Y v A s these machine/shave increased in size and height, :serious i problems of transporta tion have beenV encountered. These have been generally inet by providn'gzsuperstrncture-of a knock-down, detachable or hinged type, necessarily increasing thenianuactur mg and assembly costs and rendering more and more desirable a low overheadtype of construction, Bearing in mind, however, that the proper elevation of the loading skip must of necessity correspondingly prevail in such low overheadconstructions, anongineering vproblem of no little rvmomentl is metwth,

It is the primary object of these improvements to provide a specialr skip hoisting mechanism which obtains the required skip elevation:forl readilyl charging the aggregates into the drum, in combination with a 10W Overhead superstructure which eliminates time 4Wasting adjustments on disassembling operations heretofore vrequired to Aenalvlethe machines teclear low'overheads. .Among other objects of iny invention-may be' mentioned the simplicationof the cable winding `mecha-nien), its centralization and close association With the power unit, and the provlslonfor 'variation miv the vhit-lng leverage during the elevation of the'skip;

Other and further objects and advantages 0f the inventionwillloe-hereinafter set forth andthe novel `features thereof vdeined by the appended claims.' F

In the drawings; l i l Fig, l is a fragmentary side elevation of a mixing machine having my skip hoisting mechanism applied thereto;

Fig. 2 is L front elevation thereof; and

' Fig. 3 s a fragmentary diagrammatic view showing more. particularlythe :posi- 5,1929. Serial. No. 390,578.

vtions assumedby thel'oable in the dierent positions of the skipV g i f e 'l Liliv .numerals refer to like parts in the several figures of the drawings in .WhichlO designates-a mixing drain mounted Vupon the supporting"fi-ainenll, and .12.the1oad- -ingiskip, having the angularly arranged arms 1,3,` pivoted y upon'` the. transverse axis lill 'This s liipis operated by cableineansld in k thisinstancea doublecable, although Idesire it, to be understood vthat'l do notwish lt0 be restricted to thetnse of a double cable arrangement, I prefer'tofnse twocahles, however, `for safety purposes, each of the "cables .being capable of 'sustainlng the 11151K.- f

.iinumstresses encountered in the operation ofthefapperritos. A i' One end of each ofthe cables is connected to` theffwnding drum l@ mounted at ,one end of the drinn shaft 1,7 kand passes illi- Wal'dly' therefrom over a double sheave 18 mounted at one .Side and intermediate ythe length ofthe upper frame member 19, then vforwfndly over a Wide guide shears '205 et 'one end of the Vframe, downwardly about the skip, then over the companion Wide sheave 20 at the other side of the machine, the double sheave 18', and iinally back to the Winding drum 16 onthe other end of the vshaft 17. An important feature of this arrangement resides inthe positioningof rthiscable Winding unit at a point centrally of the frame and adjacent to its base and the priine nooverl 2l, thereby centralizing the hoisting stresses Aand eliminating" the :side orune ualized stresses 'found in most apparatus 0. this type, y l `POWer istransniitted to the shaft, 17 from the pinion 22 and gear 23 on the shaft 24, n through the pinion 25 tothe gear 26 on one ino by the sheaves 2O,l 20 in relation to the connection of the cable with the skip. After the skip has reached a position corresponding to the full line position shown in Fig. l, the cable means leaves the sheaves 20, 20', which previously guided the cables and held their side reaches separated to the maximum extent, and the maj or component of the lifting force then assumes a substantially hori zontal direction. y e

When the cables leave the sheaves 20, 20',

there is an advantageous change in the leverage arm and this is of particular importance in view of the greater demand on the powerl due to the mixing action in the drum.

In Fig. 3 I have shown diagrammatically the position of the cable when the skip is in its lowermost position in full lines, and the position assumed by said cable when the skip approximately reaches the full Vline position shown in Fig. l, at which time the reaches of the cable straighten out and converge toward the rear guide sheaves 18, 18. The grooved sheaves 20, 20 hold the cable strands in proper spaced relation once they 'are brought into contact with the sheaves in the lowering movement of the skip and during the initial sector of pivotal swing of the skip when elevated. With this arrangement of the guide pulleys, it is clear that the skip may be raised to the required lextent even with a low superstructure frame such as illustrated in the drawings, and it is no longer necessary under such conditions to provide a knocklown or pivotal superstructure such as referred to hereinbefore and commonly used today in apparatus of this type. v

lVhile the specific details of construction have been herein shown and described, the invention is not confined thereto as changes and alterations may be made, without departing from the Yspirit thereof as defined by the appended claims.

l Having thus described my invention, what I claim as new and desire to secure by Letters yPatent is:

Il. In concrete mixing apparatus of the vclass described, the combination of a supporting frame, a skip pivotally mounted on said frame and in its swing adapted to rise above the frame at its outer end, cable means for swinging the skip, spaced cable winding means therefor arranged within the frame in relatively closer relation than the width of the skip at the points of connection of the cable means therewith, cable sheaves mounted at the upper part of said frame substantially in the vertical planes over the cable winding means, guide sheaves mounted upon the end of the supporting frame spaced apart a greater distance than the cable sheaves aforesaid, the distance between said guide sheaves corresponding substantially to the distance between the sides of the skip at the points of connection of the cable means therewith, said guide sheaves being engaged by said cable means in its swing to loading position and adapted tovholdthe side reaches of the cable beyond the end of the frame substantially in the spaced relation corresponding to the connection points with the skip aforesaid when the skip is in its lowermost position.

2. In concrete mixing apparatus of the class described, the combination of a superstructure frame, a skip having diverging sidesv pivoted at its inner end within the sides of the frame and adapted in its swing to rise above said frame, cable means for swinging the-skip having an operative connection with the sides of the skip remote from the narrow pivot'end thereof, winding drums for said cable means mounted between the sides of the supporting frame in relatively closer relation; than the width of the-skip at thepointsof connection of the cable means therewith, guide sheaves mounted on the top and at the end of the frame and spaced apart a greater distance than said drums, said guide sheavesbeing arranged in such spaced relation as to maintain the side reaches jof the cable -spaced apart a greater distance than that represented bythe width of that portion of the skip which passes within the planeY of the frame sides during its swing.

3. In concretemixing apparatus of the class described, the combination of a superstructure frame, a skip having diverging sides, said skip'being pivotally connected at its inner end to said frame and in its swing adapted to rise above the frame at its outer end, a relatively short drum shaft mounted substantially centrally within the frame, a winding drum mounted on each end of said Vdrum shaft, a pair of cables'connected at ltheir respective ends to said drums and at intermediate points with the sides of the skip remote from the pivot end, a pair of vpulleys mounted over the winding drums over which the cables pass to dispose the reaches of the cable in vertical planes at the central portion of the frame, and a pair of relatively wide guide sheaves mounted upon the end of the frame 'and spaced apart a greater distance than the pulleysaforesaid, said'guide sheaves-being spaced a suiiicient distance apart tomaintain the side reaches "Pf of the cables extending from the previously mentioned pulleys out of the path of travel of the sides of the skip, said guide sheaves having grooved surfaces to hold the reaches of the respective cables spaced apart.

4. In concrete mixing apparatus of the class described, thercombination of a supporting frame, a skip pivotally mounted on said frame'and in its swing adapted to rise above fthe` frame at its outer endl, cable means for swinging the skip, cable winding means therefor arran ed within the frame, l cable sheaves mounte on the frame `above the winding means over which the side reaches of the cable extend, said cable sheaves being spaced apart a less distance than the distance between the points of connection of said side reaches with the skip, guide sheaves mounted upon the end of the n supporting frame spaced apart a greater distance than the cable sheaves aforesaid, the distance between said guide sheaves corresponding substantially to the distance between the sides of the skip at the points of connection of the cable means therewith, said sheaves being engaged by said cable means in the swing of the skip to loading position and adapted to hold the side reaches of the cable beyond the end of the frame substantially in the spaced relation corresponding to the connection points with the skip aforesaid when the skip is in its lowermost position.

In testimony whereof I aiiiX my signature.

ERICH H. LICHTENBERG. 

